A problem with existing guides made of guide ribs and guide grooves for a pushbutton is the tendency for the pushbutton to jam when the lengths of the guides are short. Tilting of a rectangular-shaped pushbutton having a long length and a narrow width that is supported within an opening of a housing may result in jamming of the pushbutton in the housing. This is particularly the case when the lengths of linear guides formed on the narrow width sides of the pushbutton are short in comparison to the length of the pushbutton.
Regardless of possible jamming, tilting of the pushbutton also results in an altered actuation feel due to changed actuating paths and actuating forces. Based on experience, unacceptably high friction and high actuating forces result when the length of a linear guide formed from a guide rib and a guide groove is shorter than one-half of the overall length of the pushbutton. Designing a comfortably actuatable pushbutton having a relatively large longitudinal extension (i.e., a large overall length) thus requires a relatively long length linear guide. This results in a relatively large installation height of the pushbutton switch. In many cases, however, a large installation height is undesirable.
Space bars on computer keyboards form pushbuttons having a large longitudinal extension in comparison to the actuating path. For such a pushbutton, eccentrically supported wire clips are often used which stabilize the pushbutton. A disadvantage of this approach is the relatively low bending and torsional rigidity of such wires and the long paths in the force action chain. Both properties result in tilting of the pushbutton at higher actuating forces.